Bottom Line:
Mast cells have a widespread distribution and are found predominantly at the interface between the host and the external environment.Conversely, mast cell dysfunction has pointed to these cells as the main offenders in several chronic allergic/inflammatory disorders, cancer and autoimmune diseases.This review summarizes the current knowledge of mast cell function in both normal and pathological conditions with regards to their regulation, phenotype and role.

Mentions:
First described by Paul Ehrlich in 1878 (Ehrlich 1878), mast cells have been viewed, for the most part, as effectors of allergy, particularly in the early and acute phases of allergic reactions. Early research on these cells relied on morphological features (Fig. 1) to identify their distribution in physiological and pathological states. The functional implications of Ehrlich’s initial view of mast cells, as metachromatic, granulated cells implicated in the nutrition of the surrounding tissue evolved gradually. In 1937, Holmgren and Willander (1937) first observed that tissues that displayed a great number of “Ehrlichschen Mastzellen” (mast cells) were enriched in heparin. The following 15 years witnessed the establishment of a relationship between mast cells, histamine, and anaphylaxis, which was supported by the discovery that histamine was present in mast cells (Riley and West 1952) and released, along with heparin, during anaphylactic shock (Rocha e Silva 1947).

Mentions:
First described by Paul Ehrlich in 1878 (Ehrlich 1878), mast cells have been viewed, for the most part, as effectors of allergy, particularly in the early and acute phases of allergic reactions. Early research on these cells relied on morphological features (Fig. 1) to identify their distribution in physiological and pathological states. The functional implications of Ehrlich’s initial view of mast cells, as metachromatic, granulated cells implicated in the nutrition of the surrounding tissue evolved gradually. In 1937, Holmgren and Willander (1937) first observed that tissues that displayed a great number of “Ehrlichschen Mastzellen” (mast cells) were enriched in heparin. The following 15 years witnessed the establishment of a relationship between mast cells, histamine, and anaphylaxis, which was supported by the discovery that histamine was present in mast cells (Riley and West 1952) and released, along with heparin, during anaphylactic shock (Rocha e Silva 1947).

Bottom Line:
Mast cells have a widespread distribution and are found predominantly at the interface between the host and the external environment.Conversely, mast cell dysfunction has pointed to these cells as the main offenders in several chronic allergic/inflammatory disorders, cancer and autoimmune diseases.This review summarizes the current knowledge of mast cell function in both normal and pathological conditions with regards to their regulation, phenotype and role.